package com.zhou.filter;

import com.zhou.pojo.User;
import com.zhou.utils.Constants;

import javax.servlet.*;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class SysFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //从session中获取用户
        User user = (User)request.getSession().getAttribute(Constants.USER_SESSION);
        if(user == null){ //未登录或者已注销
            response.sendRedirect(request.getContextPath()+"/login.jsp");
        }
        else{
            filterChain.doFilter(servletRequest, servletResponse);
        }
    }

    @Override
    public void destroy() {

    }
}
